This investigation is concerned with evaluating an instructional method based on Ausubel's description of expository teaching using advance organizers (AO) lessons. AO lessons are a method used to increase retention and transfer by identifying the general ideas that form the structure of a subject matter area. This study distinguishes between AO lessons which presented content concepts, those which presented process concepts (rules for classification), and those which combined both. Subjects were 237 rural elementary public school children. Within each grade, subjects were assigned to one of three experimental groups, or a control group: some received organizers which taught social studies (content) concepts while viewing slides depicting these concepts; some received organizers which taught rules for classification (process concepts) and were asked to apply these rules by classifying picture cards illustrating particular social studies concepts; some were given a combination of the two. Control subjects were given an introductory lesson consisting of factual information. Each group received a pretest and a posttest on classification skills. Results indicated that process organizers have a greater influence on task performance than did subject (content) organizers; however, a combination of the two is more likely to produce improved classification task performance than either type separately. (Author/JK)